Individual effectiveness in performing physical tasks frequently depends upon an individual's visual skills, such as acuity, contrast-sensitivity, and depth perception. For example, skilled crafts such as welding, cabinetmaking, and jewelry making require accurate perception of objects. Recreational activities such as team and individual sports as well as outdoor recreational pursuits such as mountain climbing and hunting rely on visual performance. For most individuals, visual acuity is readily correctable with corrective eyewear, contact lenses, or surgical techniques. Unfortunately, such correction generally does not improve visual skills other than acuity. For many activities, enhancement of skills such as color-contrast sensitivity and depth perception beyond the normal range of vision is desirable.
For some activities, protective eyewear or other vision protection is necessary. Such vision protection typically reduces or eliminates the possibility of activity-specific injuries or activity-specific exposure to reagents, intense light fluxes, or light fluxes in particularly harmful wavelength ranges. For example, dark tinted lenses can be used to reduce exposure to intense light fluxes characteristic of welding, or goggles can be used to protect the eyes from injuries in sports such as basketball that involve risk of physical contact. While such protective eyewear can prevent eye injuries, the eyewear often interferes with or degrades various visual skills.
Stephens et al., U.S. Pat. No. 4,952,046, disclose protective eyewear based on lenses that exhibit a sharp-cut spectral transmittance that substantially eliminates all incident radiation at wavelengths shorter than 515 nm and transmits substantially all incident radiation at wavelengths greater than 636 nm. The radiation at wavelengths shorter than 515 nm that is removed by these lenses has been implicated in senile macular degeneration and snow blindness, so that these lenses provide protection against these conditions.
Specially adapted optical filters have been suggested that transmit more light at wavelengths overlapping a wavelength range in which a colored object reflects or emits light. See, for example, Moore et al., PCT App. No. PCT/US96/19761. In one example, Moore et al. suggest applying a blue dye to a transparent lens for enhanced viewing of an optic yellow tennis ball.
The eyewear of Stephens et al. and Moore et al. are intended to improve eye safety and enhance object visibility. Nonetheless, such eyewear exhibit numerous limitations and improved filters and eyewear are needed.